| Unknown River - Recreation Pond | NH | Impoundment | Not Supporting | 1 | 0.02 |
| Unknown River - Recreation Pond | NH | Impoundment | Not Supporting | 1 | 0.10 |
| Upper (North) Island | MN | Lake, Freshwater | Not Supporting | 1 | 104 |
| Upper Ammonoosuc River - Brooklyn Dam | NH | Impoundment | Not Supporting | 1 | 24 |
| Upper Ammonoosuc River - Godfrey Dam | NH | Impoundment | Not Supporting | 1 | 9.82 |
| Upper Ammonoosuc River - Red Dam | NH | Impoundment | Not Supporting | 1 | 30 |
| Upper Ammonoosuc River - Weston Dam | NH | Impoundment | Not Supporting | 1 | 27 |
| Upper Artichoke Reservoir | MA | Lake, Freshwater | Not Supporting | 1 | 123 |
| Upper Baker Pond | NH | Lake/Reservoir/Pond | Not Supporting | 1 | 165 |
| Upper Baker Pond - Camp Merriwood Beach | NH | Lake/Reservoir/Pond | Not Supporting | 1 | 1.38 |
| Upper Baker Pond - Camp Moosilauke Beach | NH | Lake/Reservoir/Pond | Not Supporting | 1 | 1.38 |
| Upper Banjo Pond | MA | Lake, Freshwater | Not Supporting | 3 | 11 |
| Upper Beech Pond | NH | Lake/Reservoir/Pond | Not Supporting | 2 | 144 |
| Upper Blue Basin | TN | Lake, Freshwater | Not Supporting | 4 | 1,650 |
| Upper Bottle | MN | Lake, Freshwater | Not Supporting | 1 | 326 |
| Upper Brown Lake, Santa Maria Reservoir, Rio Grande Reservoir, Beaver Creek Reservoir. | CO | Lake/Reservoir/Pond | Fully Supporting | 0 | 1,799 |
| Upper Buckatabon Lake | WI | Lake, Freshwater | Not Supporting | 1 | 493 |
| Upper Carter Pond | NH | Lake/Reservoir/Pond | Not Supporting | 2 | 1.12 |
| Upper Cassadaga Lake | NY | Lake/Reservoir/Pond | Not Supporting | 1 | 103 |
| Upper Chandler Pond | MA | Lake, Freshwater | Not Supporting | 1 | 8.00 |
| Upper Chateaugay Lake | NY | Lake/Reservoir/Pond | Not Supporting | 1 | 2,564 |
| Upper Comstock | MN | Lake, Freshwater | Not Supporting | 1 | 267 |
| Upper Cormorant | MN | Lake, Freshwater | Not Supporting | 1 | 898 |
| Upper Cullen | MN | Lake, Freshwater | Fully Supporting | 0 | 418 |
| Upper Dam Pond | RI | Lake, Freshwater | Not Supporting | 2 | 20 |
| Upper Damon Reservoir | NH | Lake/Reservoir/Pond | Not Supporting | 1 | 49 |
| Upper Danforth Pond | NH | Lake/Reservoir/Pond | Not Supporting | 3 | 45 |
| Upper Dean | MN | Lake, Freshwater | Not Supporting | 2 | 248 |
| Upper Dianne Lake | FL | Lake, Freshwater | Fully Supporting | 0 | 47 |
| Upper Eau Claire Lake | WI | Lake, Freshwater | Fully Supporting | 0 | 1,024 |
| Upper Eggleston Reservoir. | CO | Lake/Reservoir/Pond | Fully Supporting | 0 | 30 |
| Upper Enterprise Reservoir | UT | Lake, Freshwater | Not Supporting | 3 | 353 |
| Upper Estuary | MN | Lake, Freshwater | Not Supporting | 7 | 1,129 |
| Upper Freeses Pond | NH | Lake/Reservoir/Pond | Not Supporting | 2 | 30 |
| Upper Goodwin Point Pond | NH | Lake/Reservoir/Pond | Not Supporting | 3 | 34 |
| Upper Greeley Pond | NH | Lake/Reservoir/Pond | Not Supporting | 3 | 2.36 |
| Upper Gresham Lake | WI | Lake, Freshwater | Fully Supporting | 0 | 362 |
| Upper Gull | MN | Lake, Freshwater | Fully Supporting | 0 | 418 |
| Upper Hall Pond | NH | Lake/Reservoir/Pond | Not Supporting | 2 | 22 |
| Upper Hay | MN | Lake, Freshwater | Not Supporting | 1 | 592 |
| Upper Holly Lake | WI | Lake, Freshwater | Not Supporting | 1 | 33 |
| Upper Hurricane | VT | Lake, Freshwater | Fully Supporting | 0 | 4.00 |
| Upper Kaubashine Lake | WI | Lake, Freshwater | Fully Supporting | 0 | 181 |
| Upper Kelly Lake | WI | Reservoir | Not Supporting | 1 | 13 |
| Upper Kimball Lake | NH | Lake/Reservoir/Pond | Not Supporting | 2 | 168 |
| Upper Kimball Lake | WI | Lake, Freshwater | Fully Supporting | 0 | 42 |
| Upper Klamath Lake | OR | Lake/Reservoir/Pond | Not Supporting | 7 | 62,130 |
| Upper Lake Park Beach, Lake Michigan | WI | Great Lakes Beach | Not Supporting | 1 | Filed in miles |
| Upper Lightning | MN | Lake, Freshwater | Not Supporting | 1 | 708 |
| Upper Long Lake (Upper) | IN | Lake, Freshwater | Not Supporting | 1 | 86 |